1. Field of the Invention
The present invention relates generally to glass cutters and, more particularly, to a manually operable glass cutter and an accessory thereto.
2. The Prior Art
Manually operable glass cutting tools have been known and in use for many years. Such tools generally comprise an elongated handle having notches formed therein for breaking off narrow pieces of glass after a cut has been made, and a cutting wheel rotatably mounted at one end of the handle. See U.S. Pat. Nos. 565,493 and 742,179. Special tools for cutting glass tubes or rods also have been developed, see U.S. Pat. No. 1,375,958. In precision glass cutting, such as when fitting small pieces of intricate shapes of stained glass together, two factors are of paramount importance: the requirement of maintaining a constant pressure and the requirement of moving the tool by hand in a controlled and precise manner. All the while, it also is important to guard against user's fatigue of the arm, the wrist and more particularly of the fingers. The use of compression springs has been developed to indicate to the user the necessary amount of pressure required for a clean cut in the sheet of glass along the length of the score line. See U.S. Pat. Nos. 2,516,668, 3,392,445 and 4,110,907. As for precisely guiding the cutting tool by hand, one worker in the field suggests the use of a spheroridal hand grip (U.S. Pat. No. 2,516,668), another the use of a tailored grip of high density material together with a contoured palm rest to increase the cutting pressure (U.S. Pat. No. 4,215,472), and still others the use of rings for the index or middle finger (U.S. Pat. Nos. 4,224,738 and 1,547,451).
Although these patents show or suggest some features which may be added to glass cutting tools, there is a need for an improved glass cutter which is capable of providing additional useful features.